Advances in semiconductor manufacturing technology have resulted in ever decreasing physical dimensions for the various circuit elements, such as, for example, field effect transistors, which are used in forming integrated circuits (ICs). Many ICs in a given electronic device have different functions and can operate at different frequencies. Typically, all ICs and/or all parts of a given IC may receive a voltage potential that is substantially uniform. However, as the market for consumer electronics is constantly improving, there is an increasing demand for smaller circuit packages that operate at increased speeds and consume less power for the purpose of conserving battery-life, such as in wireless communication applications. As such, one method of conserving power is to operate different ICs, or even different portions of a single IC, with a voltage that is optimized for an application use. Accordingly, power is conserved in the electronic device by not applying more than sufficient power for a given one or more of the ICs, according to the application use.
The voltage applied to a given IC for a given application use may be determined during production testing. However, environmental changes and process variations may change operating characteristics for the given IC, even subsequent to production testing of the given IC. For example, the frequency of the given IC for the given operation may vary with changes in temperature. Meanwhile, differences in transistor strength and performance variations may dictate different characteristic values that affect the operating frequency from one IC to another for the given application use.
In addition, through switching of semiconductor devices, the semiconductor material from which the semiconductor devices are made ages. As the semiconductor material of the IC ages, the transistors formed therein may be subject to deleterious effects. For example, PMOS transistors may be subject to negative biased temperature instability (NBTI), such that larger DC gate-to-source voltages are required for activation of the PMOS transistors. As another example, NMOS transistors may be subject to channel hot carrier (CHC) effects, such that the NMOS transistors can be affected with higher slew, resulting in slower switching transitions at constant bias voltages. Due to the aging effect, higher voltage levels may be required for the transistors of the IC to operate with the same performance as during production testing.
Therefore, there is a need for providing a management system capable of optimizing performance, thermal characteristics and power consumption of ICs.